Hello
I have the mavic platinum and the phantom 4 pro and thinking of buying the crystal sky 7.85 inch monitor.

Can someone recommend to buy or not .
Is it working well with above controllers?

And most important : does video lag /bad  image transmission occur? I am using now ipad mini 4 and videofeed is bad , so i wonder if i purchase the cs if this will happen too?

DOES NOT BUY  IT IS A LOST OF MONEY. WORKS WORST THAN IPAD

For me it is a fantastic device and I certainly do not regret the purchase. The only thing that disappoints me right now is the fact that it is not yet updated to GO 4 version 4.2.4 and I therefore cannot use it with my Mavic Air until the update will come.

On balance don't buy the Ultra, still some issues to ironed out. From some reason latest versions of DJI Go 4 are not supported even though they are available on IOS and Android platforms.

I would wait until the next version of the Ultra, current version has a tendency of overheating and there has been quite a few panel failures.

If you do buy, buy from a local official DJI distributor or retailer just in case you have to do a warranty return otherwise it could be messy.

For the short time it works before overheating it is very good.

For me personally it´s THE single most exciting piece of equipment I ever bought from DJI. Now I can fly in cold weather and bright sun where there is no shade. Both which was not possible before so a gamechanger personally. You will read a lot thread from owners that are quiet bitter, I don´t really understand why. All new product have some wrinkles that needs to be ironed out. The important thing is to understand what the purpose ocf the CrystalSky is, and what it´s not. I got the 5.5" with the DJI mount for the Mavic. It´s one solid well engineered combo that feels rock solid. Makes me feel like a pro. The screen can be enhanced in different modes and I find that valuable. Since I´m flying in LOG the screen is usually very bleek and low in contrast. Now I can se stuff much clearer. And the battery time, never have to depend on my iPhone or iPad again. The connections possible like HDMI out. The sd cards slots that let me backup my memory card from the drone. It goes on and on really. I can warmly recommend you to by the CrystalSky.

I bought an ultra in late December.  It failed in early January (backlight).  I sent it in for repair and they sent me a refurbished unit in early February and it also failed after 10 minutes of use (backlight).  I can't speak for anyone else but I've had nothing but trouble with the CS Ultra.